Reference page — cumulative record through Monday, October 19, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.

CVE-2021-26829

CVE-2021-26829MEDIUM

n/a n/a — OpenPLC ScadaBR

  AV  AC  PR  UI  S  C  I  A   CVSS    EPSS   %ile   KEV
   N   L   L   R  C  L  L  N    5.4   .4805   98.8   YES

AFFECTED
  Product  Versions  Fixed
  n/a      n/a –     —

TIMELINE
  Feb 5   Reserved by mitre
  Jun 11  Published (CNA: mitre)
  Nov 28  Added to CISA KEV, remediation due 2025-12-19

CWE-79 · CNA: mitre · CVSS v3.1 · 4 references · KEV due December 19, 2025

Description

OpenPLC ScadaBR through 0.9.1 on Linux and through 1.12.4 on Windows allows stored XSS via system_settings.shtm.

Lifecycle

Complete event history — 3 events, chronological
Date	Event	Detail
February 5, 2021	Reserved	Reserved by mitre
June 11, 2021	Published	Published (CNA: mitre)
November 28, 2025	KEV ADDED	Added to CISA KEV, remediation due 2025-12-19

Affected

Affected products and packages — 1 row
Vendor	Product / Package	Ecosystem	Version introduced	Fixed
n/a	n/a	—	n/a	—

Weaknesses

CWE-79

References (4)

http://forum.scadabr.com.br/t/report-falhas-de-seguranca-em-versoes-do-scadabr/3615/4 [x_refsource_MISC]
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-26829 [government-resource]
https://www.forescout.com/blog/anatomy-of-a-hacktivist-attack-russian-aligned-group-targets-otics/ [third-party-advisory]
https://youtu.be/Xh6LPCiLMa8 [x_refsource_MISC]

Authoritative record: CVE-2021-26829 at cve.org

Weaknesses: CWE-79

About this page

This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2021-26829 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Monday, October 19, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.